MiTAC 7521 PLUS/N - Manual (Page 108)

107
7521 7521 Plus / N N/B MAINTENANCE Plus / N N/B MAINTENANCE
Symptom: Symptom:
When the power button is pressed, nothing happens, no fan activi When the power button is pressed, nothing happens, no fan activi ty is heard and power indicator is not light up ty is heard and power indicator is not light up .
8.1 NO POWER:
.
CONTINUE
2. Check the power source
from AC adapter. (PJ501)
PL501
PF501
PC2 PC509 PR15 PR16
PD501 PR14 PD3
PU2 PR13 ……..
SIGNAL: PARTS:
ADINP
LEARING
POWER
OK?
END
NO
If “D/VMAIN”
failure.
CHECK: PD3,PD4,PL3,PR20,PR21,PQ12,
PU9,PR23,PC58,PC57…….
CHECK : PD1,PD2,F2,U32,C247,Q22....
If “VDD5”
failure.
If “VCC_CORE”
(CPUVCC)
failure.
CHECK: PL12,PU18,PU12,PU19,PU20,
PU22,PU23,PL11,PD21,PR79,
PR80,PC122,PC119,PC123,….
CHECK : PU10,PQ502,PQ503,PQ7,
PQ9,PL504,PD505,PU501,
PD502,PL503,PR1,PL502,
PR3,PD504…….
If “+S12V, +S5V_P
or +S3V_P” failure.
YES
CHECK: PU14,PU4,PU5,PD7,PD8,PD10,
PD11,PD15,PL5,PL6,PR32,PR35
,PR46,PR47,PR41,PR42….
If “1.5V, 1.8V”
Failure.